1
WB JEE 2023
MCQ (Single Correct Answer)
+1
-0.25
Change Language

Two base balls (masses : m$$_1$$ = 100 g, and m$$_2$$ = 50 g) are thrown. Both of them move with uniform velocity, but the velocity of m$$_2$$ is 1.5 times that of m$$_1$$. The ratio of de Broglie wavelengths $$\lambda$$(m$$_1$$) : $$\lambda$$(m$$_2$$) is given by

A
4 : 3
B
3 : 4
C
2 : 1
D
1 : 2
2
WB JEE 2022
MCQ (Single Correct Answer)
+1
-0.25
Change Language

The number of unpaired electron in Mn2+ ion is

A
2
B
3
C
5
D
6
3
WB JEE 2022
MCQ (Single Correct Answer)
+1
-0.25
Change Language

The de-Broglie wavelength ($$\lambda$$) for electron (e), proton (p) and He2+ ion ($$\alpha$$) are in the following order. Speed of e, p and $$\alpha$$ are the same

A
$$\alpha$$ > p > e
B
e > p > $$\alpha$$
C
e > $$\alpha$$ > p
D
$$\alpha$$ < p > e
4
WB JEE 2022
MCQ (Single Correct Answer)
+1
-0.25
Change Language

In Bohr model of atom, radius of hydrogen atom in ground state is r1 and radius of He+ ion in ground state is r2. Which of the following is correct?

A
$${{{r_1}} \over {{r_2}}} = 4$$
B
$${{{r_1}} \over {{r_2}}} = {1 \over 2}$$
C
$${{{r_1}} \over {{r_2}}} = {1 \over 4}$$
D
$${{{r_2}} \over {{r_1}}} = {1 \over 2}$$
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